**2.1 Step 1. Organic source selection**

Oganic sources can be from different manures: bovine, poultry, sheep, goat, pork, etc. They must ensure the absence of microorganisms through effective composting and laboratory analysis to support it [2]. They must also have low heavy metal content, below the legal limits of each country. These requirements will be retaken in a space later.

**77**

**Figure 2.**

*compost extract.*

R2

*Nutritive Solutions Formulated from Organic Fertilizers DOI: http://dx.doi.org/10.5772/intechopen.89955*

material, during the composting process [4].

The concentrate is obtained from the solid organic materials, the main ones, which are the focus of this chapter, as follows: tea, leachate, extract, and digestate. Compost tea: A "cold brewing" process, allowing growth of the organisms

Compost leachate: Water that drains, by oversaturation (excess moisture) of the

Digestate: Material remaining after various digestion processes have been applied to biomass or waste products such as animal manure, sewage sludge, and urban waste [1]. The concentrate can be obtained for unique extraction and sequential

The ratios of solid and extracting organic material (usually water) are from 1:2 to 1:10; in a v:v ratio, rest times vary, typically from 8 to 48 h. The main parameter to measure is the electric conductivity (EC) of the solutions obtained and may vary due to the organic substrate, solid and extracting ratios, incubation time, and temperature of the solution, mainly (**Figure 2**). In 2013, González and colleagues studied the EC's relationship with the origin of vermicompost used in extraction (grass plus sheepman and more manure of sheep and cattle), the water/vermicompost ratio (1:2, 1:4, and 1:6), and the time (8, 16, and 24 h). They conclude that the origin of vermicompost has a high correlation with the EC, the ratio 1:2 (vermicompost/water) offers the advantage of obtaining concentrated teas with EC values,

**Table 1** shows the total dissolved salts in a single extraction and **Table 2** for sequential extraction. It is observed that with sequential extraction it is possible to extract more dissolved solids than simple extraction, but more time is required.

**Figure 3** shows the electrical conductivity of sequential extraction with poultry and bovine compost and water. The test was performed by mixing the compost with distilled water in a 1:2 (v/v) ratio with 48 h rest time between each extraction. The dynamics of the curve show that the soluble ions (measured by the EC) are released by describing a negative exponential function; the correlations had determination ratios of

*EC that we obtained in five ratios dilution: 1:2, 1:4, 1:6, 1:8, and 1:10, with 24 h of rest in bovine and poultry* 

= 0.9042, in hen and bovine, respectively. The curves are stabilized

Extract: It is the product of passing water through the compost [4].

and the most suitable incubation time for tea extraction is 8 h.

**2.2 Step 2. Obtaining of concentrate**

extracted from the compost [3].

extraction.

**2.3 Unique extraction**

**2.4 Sequential extraction**

= 0.9388 and R2

#### **Figure 1.**

*Steps for the formulation of the ONS.*

## **2.2 Step 2. Obtaining of concentrate**

*Urban Horticulture - Necessity of the Future*

manure during the study period.

(Herrero and Thornton, 2013).

**2.1 Step 1. Organic source selection**

retaken in a space later.

in 1860 to 131.0 Tg N yr<sup>−</sup><sup>1</sup>

**2. Formulation of the organic nutrient solution**

21.4 Tg N yr<sup>−</sup><sup>1</sup>

and nutrients.

trend (0.7 Tg N yr<sup>−</sup><sup>1</sup>

This chapter focuses on manure, which is often the most available in the world's producing areas and is an important source of macro- and microelements for plant. For example, global manure nitrogen (N) production increased from

These authors mention that cattle dominated the nitrogen production of manure and contributed 44% of total manure nitrogen production in 2014, followed by goats, sheep, porks, and poultries. The application of nitrogen from manure to farmland accounts for less than one-fifth of the total nitrogen production of

Manure nitrogen production is expected to increase in the coming decades due to the growing demand for livestock populations as a result of increased human populations and changes in the structure of the diet with higher meat consumption

While, in each country, there are significant resources of organic materials as sources of plant nutrients, their commercial use in hydroponics may be feasible if there is high availability and affordable costs, and on the other hand, they must be accompanied by guarantee of safety and food safety. This production technique is very promising for food production and efficient use of water

The nutrient solution is a homogeneous mixture of water, ions (cations and anions), and oxygen that promote the growth and development of the vegetable species. Five steps are necessarily followed for the formulation of the ONS (**Figure 1**).

Oganic sources can be from different manures: bovine, poultry, sheep, goat, pork, etc. They must ensure the absence of microorganisms through effective composting and laboratory analysis to support it [2]. They must also have low heavy metal content, below the legal limits of each country. These requirements will be

, p < 0.01), according to estimates of Zhang et al. (2017).

in 2014, with a significant annual upward

**76**

**Figure 1.**

*Steps for the formulation of the ONS.*

The concentrate is obtained from the solid organic materials, the main ones, which are the focus of this chapter, as follows: tea, leachate, extract, and digestate.

Compost tea: A "cold brewing" process, allowing growth of the organisms extracted from the compost [3].

Compost leachate: Water that drains, by oversaturation (excess moisture) of the material, during the composting process [4].

Extract: It is the product of passing water through the compost [4].

Digestate: Material remaining after various digestion processes have been applied to biomass or waste products such as animal manure, sewage sludge, and urban waste [1].

The concentrate can be obtained for unique extraction and sequential extraction.

### **2.3 Unique extraction**

The ratios of solid and extracting organic material (usually water) are from 1:2 to 1:10; in a v:v ratio, rest times vary, typically from 8 to 48 h. The main parameter to measure is the electric conductivity (EC) of the solutions obtained and may vary due to the organic substrate, solid and extracting ratios, incubation time, and temperature of the solution, mainly (**Figure 2**). In 2013, González and colleagues studied the EC's relationship with the origin of vermicompost used in extraction (grass plus sheepman and more manure of sheep and cattle), the water/vermicompost ratio (1:2, 1:4, and 1:6), and the time (8, 16, and 24 h). They conclude that the origin of vermicompost has a high correlation with the EC, the ratio 1:2 (vermicompost/water) offers the advantage of obtaining concentrated teas with EC values, and the most suitable incubation time for tea extraction is 8 h.

**Table 1** shows the total dissolved salts in a single extraction and **Table 2** for sequential extraction. It is observed that with sequential extraction it is possible to extract more dissolved solids than simple extraction, but more time is required.

### **2.4 Sequential extraction**

**Figure 3** shows the electrical conductivity of sequential extraction with poultry and bovine compost and water. The test was performed by mixing the compost with distilled water in a 1:2 (v/v) ratio with 48 h rest time between each extraction. The dynamics of the curve show that the soluble ions (measured by the EC) are released by describing a negative exponential function; the correlations had determination ratios of R2 = 0.9388 and R2 = 0.9042, in hen and bovine, respectively. The curves are stabilized

#### **Figure 2.**

*EC that we obtained in five ratios dilution: 1:2, 1:4, 1:6, 1:8, and 1:10, with 24 h of rest in bovine and poultry compost extract.*


*\* Ratio solid material: volume of water applied.*

*\*\*Volume of water recovering from applied; the remaining percentage is retained by the solid phase.*

*§ The mg of salts dissolved per liter of liquid concentrate (factor 0.6 was used to convert from dS m<sup>−</sup><sup>1</sup> to mg L<sup>−</sup><sup>1</sup> )*

#### **Table 1.**

*Content of dissolved salts extracted (a single extraction with 24 h rest).*


*\* Ratio solid material: volume of water applied*

*\*\*Volume of water recovering from applied; the remaining percentage is retained by the solid phase.*

*§ The mg of salts dissolved per liter of liquid concentrate (factor 0.6 was used to convert from dS m<sup>−</sup><sup>1</sup> to mg L<sup>−</sup><sup>1</sup> ) §§Accumulated rest time*

#### **Table 2.**

*Salt content dissolved by sequential extraction (eight extractions in the same material with 48 h of rest between each extraction).*

from the fifth extraction between 1.2 and 1.8 dS m<sup>−</sup><sup>1</sup> and continue with little variation until the eighth extraction. The ion balance, between the solid and aqueous phase of the mixtures, allows organic materials to be used as a source of nutrients for plants.
